1. Field of Invention
This invention relates generally to manually-operated, multi-fluid dispensers, and more particularly to a dispenser in which hair dye ingredients are automatically intermixed and effectively metered before being discharged under pressure from at least two separate containers. The flow rate and flow ratio of the final composition provide the user with greater control and ease over application of the composition. Additionally, the critical dimensions of the dispenser orifices provide a precise metering system which produces a hair dye composition with superior mix (i.e. precise ratio of ingredients).
2. Status of Prior Art
A variety of materials have been packaged in containers under pressure for subsequent dispensing through a manually controlled valve outlet. In some cases, it is desirable that the product to be dispensed be formed or produced by interaction, at the time of dispensing, of two different ingredients which are stored separately from each other. Among such products are foods, paints, insecticides, cosmetic compositions, therapeutic agents, hair or skin-treating compositions, such as hot shaving preparations, hot skin cleansers, hot hair conditioning agents, and the like which typically utilize the reaction of hydrogen peroxide with one or more ingredients of the base composition for chemical development or generating heat. It is essential in the commercialization of such products that the ingredients be held in separate containers so that they will maintain their effective properties for an indefinite period of time during storage. The second component (i.e. Hydrogen Peroxide) of the composition includes whatever other ingredients are needed to complete the desired hair or skin treating composition.
Also, the dispensing device must be capable of mixing the components or ingredients in the proper proportion and in only those amounts that are required for use at one time. The valve structure of such a device should release the two ingredients in proper proportion from their containers and in a manner enabling the mixing of the two ingredients into the desired relationship. Such requirements demand precise operating characteristics of the valve structure.
Different mixing valve arrangements are shown in U.S. Pat. Nos. 2,973,883; 3,217,936; 3,241,722; 3,272,389 and 3,325,056. While these prior devices were operative in most circumstances and enjoyed various degrees of success, the valves and dispensers were either difficult to manufacture, not fully reliable when in extended use, or else lacked convenience of operation.
In addition to the foregoing drawbacks, however, many of the prior devices lacked a precise coordination of the flow through the valves even though the valves were mechanically coupled and therefore theoretically properly timed. Or, the prior devices lacked means to prevent malfunctioning of the valves if they were not mechanically coupled. The opening and flow characteristics of these different types differed considerably, whereby the coordination suffered even though there was a mechanical coupling of the valve actuators. As a result there was at times a wasteful use of the several liquids intended to be mixed.
To the inventors' knowledge, there has been no commercialized or clearly disclosed apparatus or method for effectively co-dispensing a hair dye product. In the usual procedure of carrying out the dyeing or combined bleaching and dyeing operation, the oxidative dye base is manually mixed in a container with hydrogen peroxide and applied to the hair in a manner to ensure complete saturation of the hair, including the root portions. This method is time-consuming and subject to mixing errors leading to the development of insufficient color or hair damage through the use of excess peroxide. There is an additional possibility that, for one reason or another, the composition cannot be applied to the hair immediately after mixing but only after a period of time has elapsed. Oxidation dyes are aromatic compounds of the diamine, amino phenol or phenol type. These aromatic compounds are the dye precursors which are transformed into dye agents by condensation in the presence of a significant excess of an oxidizing agent, generally, H.sub.2 O.sub.2. Since the oxidative dye precursors begin to oxidize immediately upon exposure to atmospheric oxygen or hydrogen peroxide, an undesirable color effect may result if a partially oxidized composition is used.
There have been various proposals in the past for the packaging of oxidative hair dyeing compositions in pressurized dispensing devices for the purpose of obviating some of the disadvantages enumerated above. However, all suffered from the inability to provide a proper mix of ingredients, as well as a lack of control over the application of the product. The aerosolizing affect upon the dye composition produced a final product too volatile to easily handle.
It has now been discovered that, by effectively sizing the particular components of the valve assembly, the overall rate of flow of the final mixed composition can be automatically metered to provide a superior mix of hair dye ingredients, as well as the greatest control and ease over application of the final composition.
Accordingly, it is an object of this invention to provide an improved dispensing device and method in which two hair dye ingredients may be kept separate until immediately prior to use, and which releases the ingredients in a controlled discharge.
Another object of the invention is to provide a novel and improved dispensing control apparatus employing a single source of pressure for dispensing two hair dye ingredients in coordinated fashion.
Another object of the invention is to provide a novel and improved container for use in a dispensing device of the pressurized type which insures more uniform mixing and discharge of hair dye ingredients from that container.